Migrate usages of deprecated classes in groovy.util package to groovyxml ones. fixes #1379

[rpalcolea]

Before this PR

I noticed that trying to use the gradle plugin fails in Gradle 9.0.0-rc-3 fails with:

Caused by: java.lang.NoClassDefFoundError: groovy/util/XmlNodePrinter
        at com.palantir.javaformat.gradle.XmlUtils.updateIdeaXmlFile(XmlUtils.java:51)
        at com.palantir.javaformat.gradle.UpdatePalantirJavaFormatIdeaXmlFile.updateXml(UpdatePalantirJavaFormatIdeaXmlFile.java:60)
        at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:125)

This makes sense as groovy/util/XmlNodePrinter and other classes were deprecated back in Groovy 3.x and removed in 4.x in favor of groovy.xml package.

After this PR

The plugin uses groovy.xml artifacts and is compatible with Gradle 9.x

[palantirtech]

Thanks for your interest in palantir/palantir-java-format, @rpalcolea! Before we can accept your pull request, you need to sign our contributor license agreement - just visit https://cla.palantir.com/ and follow the instructions. Once you sign, I'll automatically update this pull request.

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Type (Select exactly one)

• Feature (Adding new functionality)
• Improvement (Improving existing functionality)
• Fix (Fixing an issue with existing functionality)
• Break (Creating a new major version by breaking public APIs)
• Deprecation (Removing functionality in a non-breaking way)
• Migration (Automatically moving data/functionality to a new system)

Description

Migrate usages of deprecated classes in groovy.util package to groovyxml ones. fixes #1379

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